Use never to assure every event type is categorized

[laurakwhit]

What was changed

• Added TypeScript never to assure every case is handled in the switch statement for categorizeEvent.
• Added additional available event type cases to categorizeEvent
• Add GitHub action for tests

Why?

Before, the compile time error for unhandled event types was ⬇️

Now there is a default case (which is more intuitive) and the error lists which types are not accounted for ⬇️

Checklist

1. Closes: n/a

2. How was this tested: n/a

3. Any docs updates needed? n/a